Rudy Giuliani, President Donald Trump's attorney and longtime adviser, has raised eyebrows over his repeated trips to Russia, Ukraine and Armenia, which have reportedly increased in frequency since Trump took office, according to a report from ProPublica.

The former New York City mayor was in Armenia last week, with local media outlets reporting that the Trump lawyer had been invited there by Ara Abramyan, an Armenian businessman who lives in Russia and played a role in helping to reconstruct the Kremlin, ProPublica reported.

As Trump's lawyer, Giuliani has been tasked with handling the ongoing special investigation into Russian election interference that continues to plague the Trump presidency.

Rudy Giuliani, former New York City mayor and current lawyer for President Donald Trump, speaks to members of the media during a White House Sports and Fitness Day at the South Lawn of the White House May 30 in Washington, D.C. The Trump lawyer is facing scrutiny over reported trips to Armenia, Russia and Ukraine.Alex Wong/Getty

Giuliani had reportedly said he was in Armenia as a private citizen, but ProPublica said that Abramyan had implied on a local TV news show that he had expected the former New York mayor to deliver a message from him to Trump.

During the trip, Giuliani attended a technology conference organized by TriGlobal Strategic Ventures, for which Abramyan serves on the advisory board.

A conference program for the event reportedly listed Giuliani as slated to participate in a panel that also included a Russian who ProPublica said is also on a U.S. sanctions list, which was imposed after Moscow's invasion of Crimea.

In 2016, Giuliani had faced intense scrutiny for his business dealings with certain companies, including his work with client TriGlobal Strategic Ventures, which, according to its website, aims to assist Western clients in furthering business interests in the emerging economies of the former Soviet Union.

At the time, The New York Times highlighted that Giuliani had ties to TriGlobal, which had reportedly provided image consulting to clients with Kremlin ties, dating back to at least 2004.

Giuliani had defended his business relationships, claiming that he had "friends all over the world."

"This is not a new thing for me," he told the Times. "When you become the mayor, you become interested in foreign policy. When I left, my major work was legal and security around the world."

During his trip to Armenia, Giuliani tweeted messages of support for Trump, claiming that "people here in Armenia think President Trump has once again restored America's leadership position."

"Many ARMENIANS want me to tell Americans that they love President Trump's dedication to making America Great Again," Giuliani said. "This will lead the world to peace and respect for human achievement and freedom."

The Trump adviser later added: "ARMENIANS want me to tell Americans that the media doesn't tell you that Armenians, and much of the world, appreciate President Trump's leadership. No political phony talk but honesty. America leading the world to peace and freedom."

While Giuliani's trips abroad do not appear to break any laws or rules, they do seem unprecedented, said Barbara McQuade, a former U.S. attorney and law professor at the University of Michigan, who told ProPublica that she could not "recall seeing anything like this before."